Assign equal damping in different modes

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vahidbarzegar
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Assign equal damping in different modes

Post by vahidbarzegar »

Hi,
How can i assign equal damping ratios in different modes?
fmk
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Re: Assign equal damping in different modes

Post by fmk »

after the eigen $N command issue:
modalDamping $ratio1 $ratio2 .. $ratioN
and you will get $ratio damping in each mode. as a suggestion(similar to PERFORM-3d suggestion) you might want to also specify some rayleigh tangent proportional damping for the modes not covered.
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